NBA commisioner, Adam Silver, spoke about several major topics ahead of All-Star Weekend, including the league’s stance on prediction markets, Silver explained that the NBA currently views prediction markets in essentially the same way as traditional sportsbook. 

“We currently are looking at prediction markets essentially in the same way that we’re looking at sports betting markets or sports betting companies. We have a rule that was collectively bargained with the Players Association that players can make, I will call them, de minimis investments in sports betting companies, and we’re applying the same rule to prediction markets.

That means their investment cannot amount to over 1 percent. In the case of Giannis, from what I understand, it’s a minuscule investment, much smaller than 1 percent. So that does not violate the rules that have been collectively bargained with the Players Association.”